Long-term efficacy of linear-scanning 808 nm diode laser for hair removal compared to a scanned alexandrite laser.

BACKGROUND AND OBJECTIVE: Alexandrite and diode lasers are commonly used for hair removal. To date, the available spot sizes and repetition rates are defining factors in terms of penetration depth, treatment speed, and efficacy. Still, larger treatment areas and faster systems are desirable. To compare the efficacy, tolerability, and subject satisfaction of a continuously linear-scanning 808 nm diode laser with an alexandrite 755 nm laser for axillary hair removal. STUDY DESIGN: A total of 31 adults with skin types I-IV received 6 treatments at 4-week intervals with a 755 nm alexandrite laser (right axilla) and a continuously linear-scanning 808 nm diode laser (left axilla). Axillary hair density was assessed using a computerized hair detection system. RESULTS: There was a significant reduction in axillary hair after the 6th treatment (P < 0.05) on both sides (left, 808 nm: hair clearance of 72.16%; right, 755 nm: hair clearance of 71.30%). The difference in reduction between the two lasers was not significant, but both were persistant at 18 months follow-up (left: hair clearance of 73.71%; right: hair clearance of 71.90%). Erythema and perifollicular edema were more common after alexandrite laser treatment, but all side effects were transient. While 62.50% of patients reported more pain in response to treatment with the new diode laser, all patients rated treatment with either laser tolerable. CONCLUSION: Treatment with either the alexandrite or the linear-scanning diode laser results in significant, comparable, persistent (at least 18 months) axillary hair reduction among individuals with skin types I-IV.

Antifungal efficacy of lasers against dermatophytes and yeasts in vitro.

PURPOSE: Approximately 2-13% of the world population suffers from onychomycosis. Recently, lasers have been introduced for treatment. However, no effect was found with in vitro laser irradiation of pathogens on agar plates. This study aimed to investigate the efficacy of laser irradiation against fungi using an alternative in vitro approach. MATERIALS AND METHODS: Lasers of 808, 980 and 1064 nm were used to heat cell culture media and a nail clipping. Trichophyton rubrum. T. interdigitale. Microsporum gypseum. Candida albicans. C. parapsilosis, and C. guilliermondii species were subcultured and subjected to laser treatments (808/980 nm: 9-27 J/cm(2), 6 ms, 12 × 12 or 12 × 50 mm and 1064 nm: 50-240 J/cm(2), 90 ms, 5-10 mm). After irradiation, the fungal elements were transferred onto agar plates using conventional and Drigalski spatulas and were incubated for 6 days. RESULTS: The highest increase in temperature was found using a 980-nm laser with a pulse duration of 6 ms and a fluence of 27 J/cm(2). The histology work-up revealed a dissection of the nail plate from the nail bed tissue after laser irradiation. Growth inhibition was only found for C. guilliermondii and T. interdigitale. All other pathogens presented only reduced growth, and C. albicans growth was unaffected. CONCLUSIONS: This study demonstrates a clear thermal effect for linear scanning 980-nm and long-pulsed 1064-nm laser systems on either nail clippings or cell culture media. Complete pathogen growth impairment was achieved if temperatures were measured above 50 °C. The results for the 1064-nm system were almost comparable to 980 nm results.

Efficacy and safety of laser shields to prevent radiant transmission onto pigmented nevi during laser epilation: an ex vivo histology study.

PURPOSE: The demand for epilation of large body areas involves using large laser spots. The emitted light causes the desired effect in follicular melanin, but it may also produce collateral effects on pigmented melanocytic nevi. To shield melanocytic lesions, several materials were tested for their capabilities to prevent transmission of alexandrite and diode laser light. MATERIALS AND METHODS: Delivered fluence of the diode laser (808 nm, 30 J/cm(2), 12 ms) and the alexandrite laser (755 nm, 30 J/cm(2), 40 ms) and transmission rates were measured for glass slides only and additional sunscreen, polyurethane (PU) foam, zinc paste, white kajal, and a wooden spatula. For each method, ten repeated measurements were conducted. An ex vivo human skin explant model was used for histological validation. RESULTS: Using zinc as an absorber reduced transmission to 8.77% (diode) and 7.99% (alexandrite laser). Respectively transmissions were measured as following: PU foam 19.25% versus 20.78%, sunscreen 19.85% versus 16.91%, white kajal 76.43% versus 71.03% and wooden spatula 8.05% versus 3.62%. Histologically, a single application of therapeutic fluences (755 nm) in uncovered congenital nevi leads to immediate formation of atypical nucleoli, a ballooning degeneration of melanocytes, and subepidermal clefting within the treated area. In the sites of the lesions that were covered by zinc paste, PU foam, sunscreen and wooden spatula, no immediate histological changes were visible. CONCLUSION: Applying a sufficient amount of zinc paste (approximately 1 g/cm(2)) onto melanocytic lesions allows complete coverage during laser epilation.

Circular directed suction technique for ablative laser treatments.

BACKGROUND: The use of ablative laser treatments is steadily increasing. A side-effect is plume, which can potentially transmit infectious material. Insufficient plume removal may lead to transmission of infectious diseases. OBJECTIVE: To introduce a newly developed circular suction technique for ablative interventions. MATERIALS AND METHODS: The new plume removal system consists of a circular master tube and four smaller suction tubes. This design guarantees plume removal around the whole treatment area. This system can be connected in principle to any common aspiration device. The suction system worked effectively with perfect satisfaction in daily routine. Its effect on skin surface temperature was evaluated using thermography and surface temperature measurements. RESULTS: The circular system removed the laser-associated plume much better than ordinary single-point plume-removal systems. Split-face investigations confirm additional benefits in terms of better skin surface cooling. CONCLUSION: The combination of providing a cool air flow during laser treatment and circular suction is a new approach for directed cooling air streams and streamed plume evacuation without obstructing the physician because of its architecture.

Treatment of plaque-type psoriasis with the 308 nm excimer laser in combination with dithranol or calcipotriol.

PURPOSE: The combination of excimer laser and topical treatment has not been studied in clinical trials. This within-patient comparison study evaluates the response rates of plaque-type psoriasis after treatment with topical only (dithranol or calcipotriol), laser only, and combination therapy with topical medication and laser. MATERIALS AND METHODS: A total of 61 patients with psoriatic plaques located at symmetric body areas (PASI ≥ 6) were screened, 59 were enrolled, 54 completed treatment and 45 completed the 6 months follow-up. Treatments with the excimer laser were performed twice weekly until resolution or a maximum of 15 treatments. Each ointment was applied on one of the test lesions, which had to be at least 10 cm apart from each other. Efficacy was rated with a modified PASI score. RESULTS: At the end of the treatment phase only one patient in both topical therapy regimens met the criteria of partial clearance (modified PASI ≤ 2). The combined therapies resulted in 23 cases of partial clearance in both treatment arms. Four areas treated with calcipotriol, respectively six areas treated with dithranol resulted in total clearance at the end of the treatment phase. The average reduction of modified PASI scores was higher in combination than in topical treatment alone (49.8% calcipotriol + excimer versus 22.9% calcipotriol, 49.7% dithranol + excimer versus 26.8% dithranol). After six months there was a total clearance of 30.5% dithranol + excimer. CONCLUSIONS: Treatment of plaque-type psoriasis with laser in combination with topical treatment is a safe and effective therapy. The best long-term results can be obtained by the application of dithranol and excimer laser.

In vivo wound healing and dermal matrix remodelling in response to fractional CO(2) laser intervention: clinicopathological correlation in non-facial skin.

PURPOSE: Ablative fractional photothermolysis is a new concept for treatment of aged skin. Despite the low frequency of side effects there are now several reports about scarring, especially in non-facial regions like the neck. Our study aimed to investigate the in vivo wound healing process and remodelling in an area prone to scarring using a fractional ablative CO(2) laser with three different energy protocols. MATERIALS AND METHODS: Six patients with photo-damaged skin received a single fractional ablative treatment using a 250-µm scanning CO(2) laser. Three areas on the neck were treated with 50, 100 and 300 mJ/microbeam at densities of 200, 150 and 100/cm(2), respectively. Biopsies were taken from untreated skin (control) and 10 minutes, 3 days, 14 days, 21 days and 28 days post-intervention. RESULTS: Fractional ablation with higher energies resulted in increased total thermal damage. Overall, 50 mJ was effective up to the superficial dermis, 100 mJ up to the mid-dermis, and 300 mJ resulted in deep dermal ablation. The intensity of lymphocytic inflammation and dermal remodelling correlated with the total amount of thermal damage. At 300 mJ, granuloma was present and persisted for at least 4 weeks as opposed to clinical healing, which was completed < 2 weeks. CONCLUSIONS: With the above-mentioned low and medium parameter settings, ablative fractional photothermolysis is safe and effective in non-facial skin. However, dermal remodelling continues for up to 4 weeks, which should be the minimum space between treatment sessions. Higher energies may induce granuloma formation, possibly a sign of an overstrained remodelling capacity.

Comparative treatment of multiple vellus hair cysts with the 2940 nm Er:YAG and 1540 nm Er:Glass laser.

Eruptive vellus hair cysts occur sporadically, hereditarily or in association with other diseases due to developmental anomalies of vellus hair follicles. Here, we report on a 41-year-old male with multiple vellus hair cysts of the forehead, who was successfully treated three times with a non-ablative, non-fractional 1540 nm Er:Glass laser on one side of his face, and with an ablative non-fractional 2940 nm Er:YAG laser on the other side, at intervals of 6-12 weeks. Over the whole treatment period of about 9 months, we could observe a marked reduction in the total number of cysts. The bigger and painful inflammatory cysts were reduced significantly. There was a slight tendency for better clinical outcome in the area in which the Er:YAG laser had been used. Clinical and histopathological findings, pathogenesis and treatment options are discussed with a review of the literature.

Update dermatologic laser therapy.

New trends in dermatological laser therapy during the last years are based on new wavelengths, concepts and treatment combinations resulting in a variety of new dermatologic indications. Fractional laser therapy of chronic actinic damage of the skin has been introduced and already represents a standard technique. The concept of fractional non-ablative and ablative laser treatment has been shown to be safe and effective. Also pigmented and vascular skin changes can be treated by this method. New, very promising concepts for laser epilation include linear scanned as well as low fluence laser systems. The first enable very short treatment times for large areas; the latter are the basis for the growing market of laser epilation devices for home use. Nevertheless, the potential of low fluence laser devices for long-term hair reduction has not been tested so far. Furthermore, no data exist on side effects resulting from repetitive application of laser light to melanocytic lesions. Laser lipolysis has been introduced as the latest, minimally invasive way of removing small localised fat deposits. The new procedure may have a great potential for liposculpture; its further development should be thoughtfully observed. The latest innovations for precise ablation are ultra-short pulsed laser systems. Femtosecond lasers avoid thermal damage at the border areas of ablation zones.

Immunohistochemical investigation of wound healing in response to fractional photothermolysis.

Despite growing clinical evidence of ablative fractional photothermolysis (AFP), little is known about the spatiotemporal molecular changes within the targeted compartments. Six subjects received three different single AFP treatments using a scanned 250 mum CO(2)-laser beam. Spatiotemporal changes of skin regeneration were estimated by immunohistochemical investigation (HSP70, HSP72, HSP47, TGFbeta, procollagen III, CD3, CD20, and CD68) in skin samples 1 h, 3 days, and 14 days postintervention. The remodeling was uniformly started by regrowth of the epidermal compartment followed by partial to complete replacement of the microscopic ablation zones (MAZ) by newly synthesized condensed procollagen III. From day 3 to 14, the number of macrophages as well as giant cells surrounding the MAZ increased. TGFbeta expression was highest 1 h to 3 days following AFP. HSP70 and HSP72 expressions were highest 3-14 days postintervention in the spinocellular layer leading to an upregulation of HSP47. AFP performed by a scanned CO(2)-laser results in an early epidermal remodeling, which is followed by a dermal remodeling leading to a replacement of the MAZ with newly synthesized (pro)-collagen. During this, an inflammatory infiltrate with CD3(+) and CD20(+) cells surrounds the MAZ. The count of macrophages and giant cells involved in the replacement of the necrotic zones seems to be crucial for wound healing.

Prognostic value and therapeutic consequences of vascular invasion in non-small cell lung carcinoma.

The prognostic relevance of blood vessel invasion (BVI) in non-small cell lung carcinoma (NSCLC) remains controversial, as is the question of whether its finding should influence therapeutic decisions after an R0 resection. One hundred and twelve cases of NSCLC were included in the study. All had been treated by potentially curative surgical resection of the primary tumor and systematic lymphadenectomy. In all cases, lymphatic metastatic spread was at its earliest stage and only one regional lymph node was involved, 27.0+/-8.9 nodes per patient being examined histologically. Most of the cases were pT2 (75.9%) and pN1 (81.3%), and all were MX/M0 and R0. 62.5% were at stage IIB, 25.9% at stage IIIA, and 9.8% at stage IIA. BVI was found in 45.5% of the tumors (V1), and 18.8% exhibited both lymphatic invasion and BVI (L1V1). Local recurrence occurred in 10.7% of the patients, distant metastasis in 24.1%, and both forms of tumor progression simultaneously in a further 7.1%. Thus 31.2% of the patients developed distant metastases by hematogenous spread (to the brain, bones, lung, adrenal, and liver, in descending order of frequency), mostly within two years of surgery. Late metastasis is not typical of NSCLC. Adenocarcinomas showed a strong tendency to be associated with a poorer prognosis than squamous cell carcinomas, probably because of their more frequent involvement of blood vessels. Five-year survival (Kaplan-Meier method) was significantly lower in V1 cases (37.2%) than in V0 cases (56.0%; p = 0.0249). Adjuvant mediastinal radiation in node-positive cases of NSCLC may prevent local recurrence but is unlikely to influence the development of distant metastases. The histological detection of BVI is of prognostic relevance and should be considered for inclusion in the staging criteria and indications for adjuvant chemotherapy.

Fractional laser skin therapy.

Modern treatment of chronically photodamaged skin provides new, minimally invasive methods for laser intervention, using fractional, non-ablative thermal energy for an induction of dermal remodeling. The clinical efficacy coupled with a minimum "down time" for the patient has directed the development of fractional ablative laser systems. Recently introduced systems are based on CO(2) and heated Er:YAG laser systems. The clinical efficacy has been tested on one prototype each and verified their effects at a microscopic level. Initial reports suggest the results are comparable to those achieved with fractional ablative systems. We review the current possibilities incorporating our personal experience. Systematic investigations of clinical outcomes with various system settings are still needed. The possible combination of ablative and non-ablative fractional technology may also lead to increased efficacy and safety of the procedure.

Skin rejuvenation by radiofrequency therapy: methods, effects and risks.

Treatment of sun-damaged skin and wrinkles is attracting increasing interest as the possible approaches expand. Recently mono- und bipolar radiofrequency devices have been introduced as new treatment options for skin rejuvenation. Initial studies have demonstrated changes in collagen content of the skin as the molecular basis of skin texture improvement. However, there are many possible risks and side effects. We describe a patient referred to us with severe facial scarring as a result of a bipolar radiofrequency treatment performed by non-medical personnel. Due to the risk of permanent tissue damage, the indications for radiofrequency interventions should be made carefully. Potential contraindications should be considered and written informed consent about all possible side effects and risk factors should be obtained. According to current knowledge, the experience of the physician using radiofrequency devices is most important in determining the outcome of this procedure. Therefore the use of radiofrequency therapy requires extensive training.

Efficacy and cosmetic results of contact gel cooling of the skin during non-ablative laser procedures.

BACKGROUND: Aesthetic laser treatments of the skin result in collateral thermal damage to the adjacent tissue if it is not cooled. A recently developed gel cooling pad is designed to be applied to the treated area and then penetrated by the laser beam during treatment. PATIENTS AND METHODS: 97 treatments of 61 patients were documented.Vascular malformations (telangiectasia, hemangioma, spider nevi, nevi flammei, scars) were treated 52 times with the LBO laser Idas (532 nm). With the alexandrite laser Arion (755 nm), 13 treatments for hypertrichosis were evaluated. Pigmentation disorders (tattoos,lentigines,segmented melanocytic hyperpla-sia, nevus of Ota) were treated 32 times with the ruby laser Sinon (694 nm). Additionally, we measured the energy of the laser systems through a glass plate with and without the hydrogel pad. Furthermore, we examined patient satisfaction as well as noting application experiences of the treating doctors. RESULTS: Our examinations showed a negligible loss of energy in clinical use, with good patient satisfaction and good cosmetic results. CONCLUSIONS: Use of the hydrogel pad is recommended during non-ablative cosmetic laser treatments of the skin.It is especially convenient for the treatment of vascular malformations of the face.